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Mass timber construction has seen a growing interest in North America and worldwide. In the US, code provisions allow mass timber buildings to be up to 82 m tall, but with floor slabs requiring a noncombustible, usually cementitious, topping over mass timber panels (MTPs). Designing the MTP and concrete topping to act compositely can increase the strength and stiffness compared to noncomposite MTP floors. Several connections are available to create composite action between an MTP and a concrete topping, with self-tapping screws being the most widely considered practice. A new test fixture and testing method were developed to characterize connection properties and facilitate the selection of fasteners most suitable for developing composite action. Three conventional self-tapping screws were experimentally investigated at the single-fastener scale. The screws were subjected to withdrawal at 90° and 45° orientations to the interface plane between the MTP and concrete. Withdrawal from both the MTP substrate and concrete topping was investigated. Three MTP materials were tested: cross-laminated timber (CLT) consisting of two different wood species and a mass ply panel (MPP). Results demonstrated that the pullout failure of the screwhead from the concrete was the limiting failure mode. Comparisons were made between the experimental results and analytical models for screw withdrawal to assess the applicability of available models to the different MTPs. These models underestimated the capacity of the tested fasteners for all samples except for the fully threaded screws. [ABSTRACT FROM AUTHOR]

Floating Catchment Area (FCA) methods are a popular tool to investigate accessibility to public facilities, in particular health care services. FCA approaches are attractive because, unlike other accessibility measures, they take into account the potential for congestion of facilities. This is done by 1) considering the population within the catchment area of a facility to calculate a variable that measures level of service, and then 2) aggregating the level of service by population centers subject to catchment area constraints. In this paper we discuss an effect of FCA approaches, an artifact that we term demand and level of service inflation. These artifacts are present in previous implementations of FCA methods. We argue that inflation makes interpretation of estimates of accessibility difficult, which has possible deleterious consequences for decision making. Next, we propose a simple and intuitive approach to proportionally allocate demandand and level of service in FCA calculations. The approach is based on a standardization of the impedance matrix, similar to approaches popular in the spatial statistics and econometrics literature. The result is a more intiuitive measure of accessibility that 1) provides a local version of the provider-to-population ratio; and 2) preserves the level of demand and the level of supply in a system. We illustrate the relevant issues with some examples, and then empirically by means of a case study of accessibility to family physicians in the Hamilton Census Metropolitan Area (CMA), in Ontario, Canada. Results indicate that demand and supply inflation/deflation affect the interpretation of accessibility analysis using existing FCA methods, and that the proposed adjustment can lead to more intuitive results. [ABSTRACT FROM AUTHOR]

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Identifying and measuring the land value uplift (LVU) impacts of rapid transit are important for a number of reasons. However, despite the general notion that rapid transit does confer positive LVU benefits, our comprehensive and critical review of more than 130 analyses across 60 studies completed in North America over the past 40 years finds significant heterogeneity in research outcomes, leaving many significant questions unanswered. Beyond high-level differences in study inputs, we argue that a fundamental source of variability is a lack of empirical specificity from the use of proximity as the dominant way in which LVU benefits are captured. This use of a proxy leads to the potential for omitted variables and unobserved relationships, and exposes previous work to the potential for misvalued results. To overcome this issue, we outline recommendations for future research, namely a recognition of relative accessibility and the possibility of LVU impacts from transit-oriented development. Incorporating measures related to these factors into LVU models can reveal their implicit prices, resulting in research that is more theoretically inclusive, empirically comprehensive, comparable, and able to provide important information to inform policy analysis and prescription. [ABSTRACT FROM AUTHOR]

• Route choice is influenced by infrastructure and streetscape. • Bicycling is perceived to be excluded from roads through policy and design. • Regular bicyclists have mixed perceptions of existing infrastructure. • Infrastructure changes should be more aligned with stronger policy changes. • Bicycling uptake may be hindered if it is not more explicitly accommodated. As cities make concerted efforts to become more bicycle-friendly through policy changes and infrastructure, it is important that such efforts ultimately support people who currently bicycle and remove barriers that may prevent more people from bicycling. Travel surveys can reveal the nature and distribution of bicycling trips, but perceptions and behaviours of bicyclists are better understood through qualitative methods. In particular, developing cycling cities are unique settings to examine how the built environment supports bicycling as changes are made to increase bicycling levels. Through semi-structured interviews, this research explores the case of Hamilton, Ontario and the factors that influence route choice from the perspective of regular bicyclists. Major themes were identified using thematic analysis: (i) exclusion from road space; (ii) infrastructure; and (iii) streetscape. Bicyclists highly value infrastructure and seek routes that minimize interactions with cars, while avoiding many arterial roads that prioritize motorists. Routes that appear to be more human-oriented or that have nature are also attractive. Many regular bicyclists report that current bicycle infrastructure does not meet their preferences. Despite building nearly half of the planned infrastructure network, our findings suggest the built environment is not perceived to be oriented to bicycling. This study provides policy and practice recommendations for developing cycling cities in North America as they transition towards established cycling cities. [ABSTRACT FROM AUTHOR]